A comparison of dual attention, eye movements, and exposure only during eye movement desensitization and reprocessing for posttraumatic stress disorder: Results from a randomized clinical trial

Background: Currently, there is controversy on the possible benefits of dual-attention tasks during eye movement desensitization and reprocessing (EMDR) for patients with posttraumatic stress disorder (PTSD). Methods: A total of 139 consecutive patients (including 85 females) suffering from PTSD were allocated randomly among 3 different treatment conditions: exposure with eyes moving while fixating on the therapist's moving hand (EM), exposure with eyes fixating on the therapist's nonmoving hand (EF), and exposure without explicit visual focus of attention as control condition (EC). Except for the variation in stimulation, treatment strictly followed the standard EMDR manual. Symptom changes from pre- to posttreatment were measured with the Clinician-Administered PTSD Scale (CAPS) by an investigator blinded to treatment allocation. Results: In total, 116 patients completed the treatment, with an average of 4.6 sessions applied. Intention-to-treat analysis revealed a significant improvement in PTSD symptoms with a high overall effect size (Cohen's d = 1.96, 95% CI: 1.67-2.24) and a high remission rate of PTSD diagnosis (79.8%). In comparison to the control condition, EM and EF were associated with significantly larger pre-post symptom decrease (ΔCAPS: EM = 35.8, EF = 40.5, EC = 31.0) and significantly larger effect sizes (EM: d = 2.06, 95% CI: 1.55-2.57, EF: d = 2.58, 95% CI: 2.01-3.11, EC: d = 1.44, 95% CI: 0.97-1.91). No significant differences in symptom decrease and effect size were found between EM and EF. Conclusions: Exposure in combination with an explicit external focus of attention leads to larger PTSD symptom reduction than exposure alone. Eye movements have no advantage compared to visually fixating on a nonmoving hand.